Hose made of thermoplastic polymer

ABSTRACT

The invention relates to a hose made of a thermoplastic polymer comprising a core and a cover provided with a reinforcement, in particular in the form of a multilayer reinforcing structure, wherein each core and cover consists of a thermoplastic polymer and wherein, according to the invention, an intermediate coupling layer is incorporated into the core and/or cover material by welding and is connected in the form of a reinforcement. The appropriated variants of the embodiment of the intermediate coupling layer are also enclosed.

The invention relates to a hose, comprising a core and a cover having anembedded reinforcement support, specifically in the form of asingle-layer or multi-layer reinforcement structure, whereby the coreand the cover consist of a thermoplastic elastomer, in each instance.

With regard to the hose structure indicated above, there is acomprehensive prior art that furthermore describes a multiplicity ofreinforcement support variants, whereby reference is made, for example,to the following references: DE 33 32 550 C2, EP 0 149 805 B1, EP 0 567115 B1, and EP 0 848 794 B1. The reinforcement support consists of atextile and/or metallic material and is based on the purpose of use.With regard to the varied purposes of use for hoses, the followingexamples can be mentioned: water hoses, compressed air hoses, oil andgasoline hoses, hoses for chemicals, steam hoses, and hydraulic hoses.

Nowadays, hoses are produced from diverse materials, for example fromrubber, plastics (PVC), and rubber/plastic compounds. The hose of thetype stated is produced from a thermoplastic elastomer (abbreviationTPE). In particular, thermoplastic elastomers on a styrene basis(TPE-S), non-crosslinked or partially crosslinked thermoplasticelastomers on an olefin basis (TPE-O), and fully crosslinkedthermoplastic elastomer on an olefin basis (TPE-V) are used. The actualproduction of a hose is state of the art today.

An appropriate TPE inner layer (core) is extruded. Now the reinforcementsupport is applied. Subsequently, the TPE outer layer is formed (mantle,cover). The problem in this production is that a combination body isproduced for technically highly demanding articles, in which theindividual layers must undergo bonding. As a rule, in the case ofplastic hoses, the combined body is produced in that the inner and outerlayer are bonded to one another by way of the thread gaps. However,there is no adhesion to the actual reinforcement support material.

At the moment when high-quality hoses are produced, however, it isnecessary to build more reinforcement supports into the hoses, andtherefore small thread gaps are obtained. This goes so far that thereinforcement support lies closely against itself, and there are nolonger any thread gaps present. In this case, it is absolutely necessaryfor the core and cover material to enter into adhesion with thereinforcement support. However, this is not possible with conventionalTPE materials.

With the background of the aforementioned problems, the hose accordingto the invention is characterized in that an adhesion-impartingintermediate layer is worked in, which can be bonded to the core and/orcover material and therefore enters into a bond with the reinforcementsupport. In this connection, bonding takes place within the scope of theproduction process.

With regard to the arrangement of the adhesion-imparting intermediatelayer, the following three variants can be used, in particular:

-   -   The adhesion-imparting intermediate layer is extruded directly        onto the core, whereby the reinforcement support is then laid        directly onto the intermediate layer.    -   The adhesion-imparting intermediate layer is extruded directly        onto the reinforcement support, whereby the cover is worked on        subsequently.    -   The adhesion-imparting intermediate layer is applied to the core        and to the cover, so that the reinforcement support is        completely bonded into the intermediate layer. This variant is        particularly advantageous, particularly if there are no longer        any thread gaps.

In the case of multi-layer hoses (EP 0 567 115 B1), theadhesion-imparting intermediate layer is applied between the individualreinforcement supports, whereby the variants mentioned above canadditionally be used.

The adhesion-imparting intermediate layer has a minimal melting point of75° C. and a maximal melting point of 170° C.

The advantageous materials with regard to the adhesion-impartingintermediate layer are:

-   -   An olefin plastic is used, particularly on the basis of        polyethylene or polypropylene. In this connection, the        reinforcement support is surrounded with twisted yarns of the        olefin plastic, or the olefin plastic is applied directly to the        reinforcement support.    -   The adhesion-imparting intermediate layer consists of a TPE        (TPE-S, TPE-O, TPE-V) and a hydrocarbon resin, particularly an        aromatic hydrocarbon resin, as well as other additives, if        necessary. The hydrocarbon resin component amounts to 2 to 50        wt.-% in this connection, particularly 5 to 30 wt.-%.    -   The adhesion-imparting intermediate layer is an acrylate        copolymer, particularly an ethylene/acrylate copolymer. In this        regard, again, the following should be particularly mentioned:        ethylene methyl acrylate (EMA), ethylene ethyl acrylate (EEA),        or ethylene butyl acrylate (EBA). A hydrocarbon resin,        particularly again, an aromatic hydrocarbon resin, as well as        other additives, if necessary, is/are mixed into the acrylate        copolymer. Here again, the hydrocarbon resin component amounts        to 2 to 50 wt.-%, particularly 5 to 30 wt.-%.    -   Here, another component in the form of a functionalized polymer        is preferably added to the adhesion-imparting intermediate        layer. This additional component is a malein anhydride graft        polyethylene or a polypropylene grafted in similar manner, or an        acrylate copolymer functionalized with polar CO groups or epoxy        groups. The proportion of the functionalized polymer is 0.5 to        20 wt.-%, particularly 2 to 10 wt.-%.    -   The adhesion-imparting intermediate layer is a hydrocarbon        resin, particularly an aromatic hydrocarbon resin. In this        connection, the hydrocarbon resin has a plastification point of        75° C. to 145° C., particularly 100° C. to 145° C.

The data given above in wt.-% relate to the total mass of theadhesion-imparting intermediate layer.

1. Hose, comprising a core and a cover having an embedded reinforcementsupport, specifically in the form of a single-layer or multi-layerreinforcement structure, whereby the core and the cover consist of athermoplastic elastomer, in each instance, wherein an adhesion-impartingintermediate layer is worked in, which can be bonded to the core and/orcover material and therefore enters into a bond with the reinforcementsupport.
 2. Hose according to claim 1, wherein the adhesion-impartingintermediate layer is extruded directly onto the core, and thereinforcement support is laid directly onto the intermediate layer. 3.Hose according to claim 1, wherein the adhesion-imparting intermediatelayer is extruded directly onto the reinforcement support, and the coveris worked on subsequently.
 4. Hose according to claim 1, wherein theadhesion-imparting intermediate layer is applied to the core and to thecover, so that the reinforcement support is completely bonded into theintermediate layer.
 5. Hose according to claim 1, wherein in the case ofmulti-layer hoses, the adhesion-imparting intermediate layer is appliedbetween the individual reinforcement supports.
 6. Hose according toclaim 1, wherein the adhesion-imparting intermediate layer has a minimalmelting point of 75° C.
 7. Hose according to claim 1, wherein theadhesion-imparting intermediate layer has a maximal melting point of170° C.
 8. Hose according to claim 1, wherein the adhesion-impartingintermediate layer is an olefin plastic.
 9. Hose according to claim 8,wherein the olefin plastic is polyethylene or polypropylene.
 10. Hoseaccording to claim 8, wherein the reinforcement support is surroundedwith twisted yarns of the olefin plastic.
 11. Hose according to claim 8,wherein the olefin plastic is applied directly to the reinforcementsupport.
 12. Hose according to claim 1, wherein the adhesion-impartingintermediate layer consists of a thermoplastic elastomer and ahydrocarbon resin, particularly an aromatic hydrocarbon resin, as wellas other additives, if necessary.
 13. Hose according to claim 12,wherein the thermoplastic elastomer comes from the group TPE-S, TPE-O,or TPE-V.
 14. Hose according to claim 12, wherein the hydrocarbon resincomponent amounts to 2 to 50 wt.-%, particularly 5 to 30 wt.-%.
 15. Hoseaccording to claim 1, wherein the adhesion-imparting intermediate layeris an acrylate copolymer.
 16. Hose according to claim 15, wherein theadhesion-imparting intermediate layer is an ethylene/acrylate copolymer.17. Hose according to claim 16, wherein the adhesion-impartingintermediate layer is a copolymer on the basis of ethylene methylacrylate (EMA), ethylene ethyl acrylate (EEA), or ethylene butylacrylate (EBA).
 18. Hose according to claim 15, wherein a hydrocarbonresin, particularly an aromatic hydrocarbon resin, as well as otheradditives, if necessary, is/are mixed into the acrylate copolymer. 19.Hose according to claim 18, wherein the hydrocarbon resin componentamounts to 2 to 50 wt.-%, particularly 5 to 30 wt.-%.
 20. Hose accordingto claim 12, wherein another component in the form of a functionalizedpolymer is added to the adhesion-imparting intermediate layer.
 21. Hoseaccording to claim 20, wherein the functionalized polymer is a maleinanhydride graft polyethylene or malein anhydride graft polypropylene, oran acrylate copolymer functionalized with polar CO groups or epoxygroups.
 22. Hose according to claim 20, wherein the proportion of thefunctionalized polymer is 0.5 to 20 wt.-%, particularly 2 to 10 wt.-%.23. Hose according to claim 1, wherein the adhesion-impartingintermediate layer is a hydrocarbon resin, particularly an aromatichydrocarbon resin.
 24. Hose according to claim 23, wherein thehydrocarbon resin has a plastification point of 75° C. to 145° C.,particularly 100° C. to 145° C.